Controlling means for hoists



1942. A. COTESWORTH ET AL 2,270,366

CONTROLLING MEANS FOR HOISTS Filed Dec. 23, 1938 ALFRED CoTEZSWO KARL.w. Srnvs Patented Jan. 27, 1942 UNITED STATES PATENT OFFICE CONTROLLINGMEANS FOR HOISTS Alfred Cotesworth, Kenmore, N. Y., and Karl W. Stinson,Columbus, Ohio, assignors to Columbus McKinnon Chain Corporation,

6 Claims.

Our invention relates in general to controlling means for hoists, andparticularly to that type of hoist which is actuated by an electricmotor forming an integral part of the structure.

It is Well known to those skilled in the art that an electric motor ofthe single-phase, split-phase type or capacitor type are best suited foruse in the manufacture of an inexpensive electric hoist. These motors,however, have a decided drawback in that it is necessary that thearmature of such motors come to a standstill before reversal ofdirection of rotation can be brought about, since too rapid a movementof the controls will cause the motor to continue rotating in its initialdirection.

One of the principal objects of our invention has been to provide adevice whereby the controls, in their movement from one position toanother to bring about a reversal of rotation, will cause sufficientdelay to permit the motor armature to come to a standstill.

Another object has been to provide a device which is not onlyinexpensive to manufacture, but may be easily applied to existing hoistswithout the necessity of redesigning or altering such hoists.

The above objects and advantages have been accomplished by the deviceshown in the accompanying drawing, of which:

Fig. 1 is an exterior view of a hoist, having portions thereof brokenaway and showing our invention applied thereto.

Fig. 2 is an enlarged, sectional elevation of our invention taken online 2-2 of Fig. 1.

Fig. 3 is an enlarged, transverse section taken on line 3-3 of Fig. 2.

Fig. 4 is a front elevation of a modified form of invention.

Fig. 5 is a longitudinal, sectional View of the form of invention shownin Fig. 4.

In the drawing, I represents the hoist which is equipped with a motor llpermanently secured to and forming an integral part of the hoiststructure. The controller switch is represented at I2. The motor isattached to the casing l3 of the hoist which is provided at the end witha cover l4. The casing contains the usual gearing (not shown) forreducing the speed of the motor shaft (not shown) to the load-lift wheel(not shown).

The control shaft of the hoist is represented at 15, and may be acontinuation of a controller switch shaft or it may be connected theretoby suitable means. Carried by the shaft I is a head It which iscylindrical in form and upon which is rotatably mounted a drum 2-0. Thedrum 2!! is preferably the same thickness as the head l6 and a drumplate 2| is secured to each side of the head, preferably by means ofbolts 22. These plates are larger in diameter than the drum and theirperipheries, therefore, extend some distance beyond the periphery of thedrum, as shown in the drawing, whereby a groove 23 is formed in thedrum. The control cords 24 and 25 of the hoist are each extended aroundthe drum in opposite directions and are secured to the periphery of thedrum 20 by any suitable means. Sufficient cord is wound around theperiphery of the drum to allow sufficient rotation of the drum to effectthe proper operation of the controller switch.

In carrying out our invention, as hereinbefore pointed out, a certainamount of lost motion is provided between the control drum and thecontrol shaft in order to delay the operation of the switch to eitherreversing position. In this form of our invention, this function iscarried out by means of an annular groove 26 formed in the periphery ofthe head I6 and extending substantially 180 around the circumference ofsaid head. A detent shoulder 30 is formed at one end of the groove and adetent shoulder 3| at the opposite end thereof. The drum carries adetent key 32 which is rigidly mounted in the drum and extends into thegroove 26, whereby the drum is free to rotate upon the head l6 until thedetent key engages with either detent shoulder 30 or 3! in the rotationof the drum.

In Figs. 4 and 5, we show our invention applied to a lever type ofcontrol where 35 represents the control lever which is formed withoutwardly extending arms 36 and 40, each having a suitable aperture 4|for the reception of control cords 42 and 43. In Figs. 4 and 5 thecontrol shaft is represented at 44, and this shaft preferably has acylindrical head 45 upon which the hub 46 of the control lever 35 ismounted. The hub of the control lever is formed in its inner peripherywith an arcuate groove 50 extending around its periphery for apredetermined distance, and formed at one end with a. detent shoulder 5|and at its opposite end with a detent shoulder 52. The head 45 of thecontrol shaft 44 is provided with a. detent key 53 which projects abovethe periphery of the head and extends into the arcuate groove 50. Thecontrol lever 35 is preferably held in position against movementoutwardly on the control shaft by means of a washer 54 through which abolt 55 is passed, and said lever is held against movehandles 6| whichare suitably secured to the lower ends of these cords.

Referring now to the form of invention shown in Figs. 1-3, inclusive, itwill'be obvious that when, for instance, the control cord 25 isoperated, the drum 20 will be rotated in clockwise direction and thedetent key 32 will freely move through the groove 2'6 until it strikesthe detent shoulder 3| of the control shaft head [6 at the right of Fig.2. The movement of the drum upon the head up to this point will be anidle movement and will perform no function except that of rotating thedrum upon the head. When, however, the key strikes the shoulder 3 I, thecontrol shaft l will be positively rotated to operate the controllerswitch. When it is now desired to reverse the hoist by pulling upon thecord 24 which will, of course, reverse the direction of rotation of thedrum, it will be seen that the detent key will move from its engagementwith the detent shoulder 3| around through the groove 26 a distancesubstantially equal to the length of the groove, whereupon the drum canthen be positively operated in the reverse direction by the engagementof the key with the opposite detent shoulder 30. During such delayed orlost motion between the drum and the head it, the motor of the hoistwill have had opportunity to come to a standstill and the desiredreversal of the motor can then be effected.

The same functions occur when operating the device shown in Figs. 4 and5. In this form, however, when the control cord 43, for instance, isoperated, the control lever will be rotated upon the head 45 and thearcuate groove 55 will move over the key 53 carried by the head untilthe shoulder 5| is engaged with the key, after which further pullingupon the cord 43 will cause the control shaft 44 to be positivelyoperated. Upon reversal, by pulling the cord 42, the groove 50 willfirst be moved over the key 53 until the opposite detent shoulder 52 isbrought in contact therewith, after which further movement of the cord42 will cause the control shaft to be positively operated in the reversedirection.

It is desirable that the control drum and the control lever be returnedto their neutral positions. In order to accomplish this, we provide areturn spring 65 on the form of invention shown in Figs. 1-3, inclusive,and a return spring 66 on the form of invention shown in Figs. 4 and 5.The spring 65 is provided with upstanding ends 61 which engage oppositesides of a lug 68 carried by the bracket 69 which is secured to thehoist. These spring ends also engage with a lug carried by one of theplates 2! of the drum. The spring 55 is mounted about the control shaftl5. The spring 66 of the other form of invention is provided withupstanding arms H which engage opposite sides of a lug 12, carried bythe cover 56 and a lug or pin 13, carried by the upstanding arm 14 ofthe control lever 35. These springs serve to keep the control drum andlever in their neutral positions. The shafts I5 and M of the two formsof inventions are maintained in neutral position by means of the Springusually provided in the controller switch. This is not shown or furtherdescribed since it does not form a part of our invention.

Having thus described our invention, what we claim is:

1. A control for single-phase, reversing electric motors of the typewhich continues its operation uni-directionally upon too rapid operationof the reversing means, comprising a control member freely movable intwo directions, manually actuated control means oscillatably mountedupon the control member for unrestrained idle relative movementtherewith through a limited path in either direction, whereby to affordtime delay in the movement of said member to its actuating positions,and interspaced detent means carried by the control member and thecontrol means for coupling said member and said means at the extremitiesof said idle relative movement to positively actuate said control memberin either direction.

2. A control for single-phase, reversing electric motors of the typewhich continues its operation uni-directionally upon too rapid operationof the reversing means, comprising a control shaft freely movable in twodirections, manually actuated control means oscillatably mounted uponthe control shaft for unrestrained idle relative movement therewiththrough a limited path in either direction, whereby to afford time delayin the movement of said shaft to its actuating positions, and detentmeans carried by the control shaft and the control means for couplingsaid shaft and said means at the extremities of said idle relativemovement to positively actuate said control shaft in either direction,said detent means being so interspaced that the idle relative movementprovides sufficient time for the motor to come to rest before theoperator can move the control member to a reversing position.

3. A control for single-phase, reversing electric motors of the typewhich continues its operation uni-directionally upon too rapid operationof the reversing means, comprising a control shaft freely movable in twodirections, manually actuated control means oscillatably mounted uponthe control shaft for unrestrained idle relative movement therewiththrough a limited arcuate path in either direction, whereby to affordtime delay in the movement of said shaft to its actuating positions, anddetent means carried by the control shaft and the control means forcoupling said shaft and said means at the extremities of said idlerelative movement to positively actuate said control shaft in eitherdirection, said detent means being so interspaced that the idle relativemovement provides sufficient time for the motor to come to rest beforethe operator can move the control member to a reversing position.

4. A control for single-phase, reversing electric motors of the typewhich continues its operation uni-directionally upon too rapid operationof the reversing means, comprising a control shaft freely movable in twodirections, a cylindrical head carried by the control shaft, manuallyactuated control means oscillatably mounted upon said head forunrestrained idle relative movement therewith through a limited arcuatepath in either direction, whereby to afford time delay in the movementof said shaft to its actuating positions, and detent means carried bythe control shaft and the control means for coupling said shaft and saidmeans at the extremities of said movement to positively actuate theshaft in either direction, said detent means being so interspaced thatthemotor will have suificient time to come to rest before the operatorcan move the control lever to its reversing position.

5. A control for single-phase, reversing electric motors of the typewhich continues its operation uni-directionally upon too rapid operationof the reversing means, comprising a control shaft freely movable in twodirections, a head carried by the control shaft, interspaced detentabutments carried by the head, a control drum oscillatably mounted uponthe head for unrestrained idle relative movement therewith through alimited arcuate path in either direction, whereby to afford time delayin the movement of said shaft to its actuating positions, and a detentcarried by the head and engageable with said detent abutments forcoupling said shaft and said drum at the extremities of said movement topositively actuate the shaft in either direction, whereby the motor willhave sufficient time to come to rest before the operator can move thecontrol lever to its reversing position.

6. A control for single-phase, reversing electric motors of the typewhich continues its operation uni-directionally upon too rapid operationof the reversing means, comprising a control shaft freely movable in twodirections, a head carried by the control shaft, said head being formedwith an arcuate groove having a detent abutment at each end thereof, adrum oscillatably mounted upon the head for unrestrained idle relativemovement therewith through a limited path in either direction, wherebyto afford time delay in the movement of said shaft to its actuatingpositions, a detent key carried by the drum and engageable with saidabutments for coupling said drum and said shaft at the extremities ofsaid idle relative movement to positively actuate said shaft in eitherdirection.

ALFRED COTESWORTH. KARL W. S-TINSON.

